Crossfire problem

[Kenkable]

Hi!

I just uppgraded my pc with some old parts i bought from a friend. My intension was to run Cross fire for better gaming experience, but i have alot og BSOD problems.

does anyone have any experiense with this?

[Specs]

Motherboard: ASUS M4A79T Deluxe

CPU: AMD Phenom II X4 965

RAM: Corsair dominator DDR3 (8GB) (Should have been 16GB, but somehow it fails, system runs without errors, evenn BIOS only register 8GB, any tips on this aswell?)

Graphics: 2x Radeon HD 5770

PSU: Cooler master Silent Pro Gold 1200w


Sorry for bad english (Norwegian writer)

 

[Kenkable]

Forgot to mention, system works good in windows, but when i launch BF3 the problems occur afet 5-10 mins of gaming